Oil burning apparatus



Jan. 28, E936. A. E. PAIGE OIL BURNING APPARATUS Filed April 7, 1930 Patented Jan. 28, 1936 UNITED STATES PATENT OFFICE 3 Claims.

My invention relates to apparatus adapted for heating buildings by combustion of petroleum distillates, in a flame which may be started with a match and thereafter maintained solely by the 5 fuel oil.

It is characteristic of my invention that the oil, in a liquid state, is progressed by gravity to the burner, and by capillary attraction in the burner, and by convection from the burner to the flame, in such a gaseous state that complete combustion thereof is effected by automatically preheating and varying the supply of air in accordance with the supply of oil to the burner.

As hereinafter described; such oil gas is produced in an annular bowl in which the liquid oil rises upon the surfaces of granular refractory wick material, preferably the volcanic clinker known as pumice stone, which is of substantially the same specific gravity as the fuel oil which percolates upwardly between its granules; the flotation of such wick material preventing its subsidence into a solid mass obstructing the passage of the oil therethrough.

During the operation of the form of my invention hereinafter described; a supply of the fuel oil suflicient to continually maintain a low flame at the top of the wick material in the bowl, is continually delivered at the bottom of said wick material, as long as any flame is maintained at the top thereof; thermostatically operative means being provided to augment and diminish both the fuel and air supply in accordance with the heating requirements. Such apparatus includes means for manually starting and stopping the operation of an air blower which is preferably electrically actuated and controlled; means for manually controlling the oil supply; means for thermostatically increasing the flow of oil to said bowl, and means for automatically stopping the flow of oil to said bowl, if and when the burner flame is extinguished.

My inventiondncludes the various novel features of construction and arrangement hereinafter more definitely specified.

In said drawings, Fig. I is a plan view of apparatus embodying my invention.

Fig. II is a vertical longitudinal sectional view of said apparatus taken on the line II, II in Fig. I.

'The apparatus shown in the drawings is adapted for use in a furnace of the air, water, or steam heating type provided with a flue connection for discharge of products of combustion, from the flame i at the top of the oil burner 5. Said burner includes the oil bowl 6 which is supplied with liquid hydrocarbon i such as petroleum distillate, through the conduit 8, 9.

The flow of fuel to said burner 6 may be manually controlled by the valve I 3 immediately adjoining the reservoir I 0 and automatically controlled by the float valve to which the fuel flows through the pipe 9 and filter I5. Saidvalve i4 is preferably constructed like the float valve in an automobile carburetor, and is operative to prevent the flow of oil to said bowl 6 above the maximum level indicated by the dotted line I! in Fig. II.

Said maximum level I! is determined to be below the top of the burner bowl 6, so as to prevent any accidental overflow thereof, but so far above 1 the level at which the oil is vaporized during its combustion in said burner 5, as to impose the desired constant hydrostatic pressure upon the oil on its way from said valve H to said bowl 6. One inch such head is sufllcient to maintain combustion of one and one-half gallons of oil per hour.

The oil I may be thus supplied to the burner 5 solely by gravitation, and caused to rise in the burner bowl 6 over granular wick material 2| preferably pumice stone or other refractory material of substantially the specific gravity of the oil and having such surface tension as to form thin films of the oil thereon, which vaporize readily, and the oil vapor, mixed with air, rises from such wick material into the flame by convection.

Although the flow of the oil I is automatically stopped by the operation of the valve M if and when it reaches the level I! in the bowl 6; it is only thus stopped if and when the flame is extinguished. The oil 1 is thus supplied at a rate which is adjustably predetermined and variable by means of three valves in the casing 23, including the two valves 24 and 25 which are of the axially adjustable screw type and respectively determine the maximum and minimum flow. Said valve 24 determines the effective area of the main oil port 26. Said valve 25 controls the effective area of a bypass which is opened and shut by said third valve which is thermostatically electrically controlled to alternately permit the maximum and minimum supply of oil to the burner. Said valve 24 is adjusted to permit the passage of the full amount of oil necessary for the maximum heating requirements of the furnace I; but said valve 25 is set to permit the passage of the minimum amount of oil sufficient to maintain a flame 4 at the burner 5.

The outer end of the casing 33 of said burner 7 is provided with a foraminous cover plate 34 which is attached to the motor housing 35 in V i which the blower motor 36 is mounted with its fan blades 31 at the outer end thereof, as shown in Fig. II, so that the air thereby supplied through said casing 33 cools said motor and is thereby preheatedbefore reaching said bowl 6.

The electrical circuits for controlling said fan "motor 36 extend through the junction box 43 on the flat top of the motor housing 35' which supports the switch 45, and include the conductor 48, resistance 49, and conductor 50, said resistance 49 being in series with the field coil of said motor 36 when it is desired to operate the fan at low speed, and being short circuited when it is desired to operate said fan,motorat h.igh

speed. Said motor is controlled in cooperative relation with said third valve, so that the simultaneous supplies of oil and air to the bowl 6 are increased and diminished in cooperative relation .to' effect complete combustion. Q

'As shown in 'Fig. II; said burner bowl 6 has the axial air tube 1'! provided with a cap 18 which is upheldin variable, axially spaced, relation therewith by three screws 19 and has ribs 89, so that air is uniformly distributed radially from said tube Tl between the top of the latter and the under surface of said cap 18. Said burner bowl 6 is suspended invariable axially spaced relationwith the air distributing ring 8|, by three screws 82 which extend through said ring in threaded engagement with the rim of said bowl. 'Saidjring has internal ribs 83 tending to impart afswirling motion to the air delivered between them downwardly past its inner flangew84 into said bowl 6, and also-has secondaryairports 86 above said bowl. Said ring 8| rests upon the top of the air jacket. 81 with its circular flange 88 depending inside of said jacket. The flame may be spread outwardly or directly upwardly in accordance with the relative adjustmentof said screws 19 and 82, for most efficient cooperation with the furnace in' which it is installed. Said jacket 81, which is conveniently formed of sheet metal, like an ordinary stove pipe, rests upon the cast iron elbow 89 which has the annular flange 98 extending upwardly therein. Said parts are held in the assembled relation shown .by'the single stove bolt 9| which has itshead 92 seated in the socket 93 in the bottom of said elbow 89, and is engaged at its upper end by said cap 18 as a nut. any desired height from the floor level 95 by Said elbow may be upheld at a single leg 96, which is merely a piece of-cylindrical stock rod slip fitted in said socket 93.

- Although said bowl 6 may be smoothly curved from the edge of said tube 11 to its rim; 'I prefer to make a circular ridge 91 intermediate of its height, which forms a shallow groove 98 in coaxialgrelation with 'said airjtube I1, and into which the oil passes from the supply conduit 8; so that when theflow of oil is reduced to the minimum, its-combustion is localized with'respect to said groove 98, although when the flow is. augmented by opening the electrically controlled valve, as above described, the oil overflows said grooveinto the lower portion of said bowl i 6 and the combustion thereof is coextensive with the area of the 'bowl which is charged with the granular wick material 2| to the level of "the top ofsaid ridge 91. The surface tension, 'or' 'capillary attraction of the surfaces, of the wick gran -ules 2&1 causes oil .to rise upwardly thereon in thin filjms which may. be lighted withoan ordi- 2,o29,1s4 if I Hi nary match flame, altho a body of the oil would extinguish an ignited match thrust therein. 7

I find it convenient to supply said jacket 81 with air under pressure thru the conduit formed by the burner'casing 33, and which is primarily a cylindrical tube of sheet metal, like a stove pipe,

but which is bent to fit over the elliptical flange I82 of said elbow 89, to which it is detachably secured by two screws I93, respectively at the top and bottom thereof. 7 The opposite end of said conduit 33 is fitted over the cylindrical annular flange I04 on said motor housing 35 to which it is detachably secured, by two screws I86, at respectively opposite sides thereof. Said housing 35, which isan iron casting, has opposite side lugs I 01. in which are drilled sockets J89 in which are respectively. slidably fitted the two legs H9 ableby set screws III, to level said bowl 5. v

Said motor housing 35 has the foraminous front closure plate 34 which maybe detachably secured thereto by the screws I I2, thus inclo'sing the air inlet chamber l l 3 and forming a screened air inlet to said casing 33, jacket 81, and burner bowl 6.

Said fan 3lis conveniently provided with the wire cage frarne H4 which is detachably connected with the motor frame by the screws ll5,.and

said motor is detachably held in said housing 35 by the resilient sleeves H6 which are carried by members of said frame I I4.

As above described, the burner 5 and its ap 'purtenances is'acompletely organized unit which may be readily installed inany ordinary furnace, after removing the furnace grate and re moving said burner leg 99 from the elbow 89, and by thrusting the structure, through the ashpit doorway, into; the desired position in the furnace, and thenraising said elbow 89, conveniently by a poker or otherlever extended through the upper doorway of the furnace combustion 'which areconveniently formed of cylindrical iron,

rods, like said leg 96, and are vertically adjustchamber, and restoring the leg 96 to the position in a flame of minimum size which it is desirable to maintain when'the thermostats are not calling for heat. Therefore, I prefer to mount both the air, blower motor 36 and the electrical resistance 49 aforesaid, within the air conduit leading to. the burner and through which the oil conduit exten ds, for the forced draft of air through said conduit not only has a desirable cooling, efiect upon both said motor and resistance, but both the air and oil are thereby preheated to such a degree as to greatly facilitate the vaporization of the oil and the intimatemixture of the air with the oil vapor, and the complete combustion of the mixture. Howeverfthe air component of the combustible mixture may be thus preheated 7 without preheating'the oil; or vice versa.

mixture'with the oil Vapor, by mounting in the 'bowla circular foraminous band I68 which ex; -tends'into the flame and through which the air 7 Moreover, the heat of combustion in the bowl 8. may be utilized to preheat the air before its from the axial air tube 11 is directed into the flame.

Therefore, I do not desire to limit myself to the precise details of construction, arrangement, or method of operation herein set forth, as it is obvious that various modifications may be made therein without departing from the essential features of my invention, as defined in the appended claims.

I claim:

1. The combination with an annular oil burner bowl, having a central air conduit; of an air jacket surrounding said bowl in spaced relation with the rim thereof, adapted to conduct air to support combustion in said bowl; air directing means overlying said bowl and respectively adapted to direct air outwardly with respect to said axis and inwardly with respect to said rim, including a cap at the axis of said bowl and supported by said central air conduit and an air distributing ring overhanging the rim of said bowl and supported by said jacket; and means respectively connecting said cap with said bowl and said bowl with said ring in variable vertically spaced relation; whereby the quantity and proportions of air delivered to said bowl, outwardly from the axis thereof and inwardly from the circumference thereof and consequently the shape of the flame produced by combustion in said bowl may be varied by relative vertical adjustment of said cap and bowl with respect to said ring.

2. In an oil burner; the combination with an open-topped annular oil bowl, having a central 5 air conduit; of a casing surrounding said bowl adapted to conduct air inwardly over the rim of said bowl to support combustion in said bowl; a cap supported at the axis of said bowl, in cooperative relation with said air conduit, adapted to direct air from said casing outwardly over said bowl, from said casing; and a screw threaded member extending axially upward through said bowl from said casing and engaging said cap as a nut; whereby said cap is secured in adjusted relation with said bowl and casing.

3. In an oil burner, the combination with an open-topped oil bowl; of an air jacket around said bowl adapted to conduct air to support combustion in said bowl; a casing member supporting said air jacket; an air distributing ring supported by said jacket overhanging the rim of said bowl; means detachably connecting said bowl with said ring, whereby said bowl is supported by suspension from said ring; and means connecting said casing member with said bowl, including a screw; whereby said bowl is held under tension between said casing and jacket.

ARTHUR. E. PAIGE. 

